1. Field of the Invention
The present invention relates to structures formed on a semiconductor substrate and to methods of forming the same, and more particularly, to scribe-line structures formed on a semiconductor substrate, to substrates having such scribe-line structures, and to methods of forming the same.
2. Description of the Related Art
Generally, multiple semiconductor devices are formed respectively on predetermined regions of a semiconductor substrate. Each of these regions may be defined by a set of intersecting scribe-lines, for example by horizontal and vertical scribe-lines. Each such scribe-line has a predetermined width, so that the semiconductor substrate can be easily cut along the scribe-lines so as to separate the individual semiconductor devices from each other and from any unused portions of the semiconductor substrate. Before performing the cutting process described above, the semiconductor devices and the scribe-lines are typically covered with a plurality of interlayer insulating layers. The interlayer insulating layers protect the semiconductor devices from exterior environment influences while cutting the semiconductor substrate.
But, in recent manufacturing operations in this field, it has been found that it is often necessary to replace each of the interlayer insulating layers used to protect the formed semiconductor devices with other materials having lower dielectric constants to avoid interfering with the higher-speed operation of modern semiconductor devices. A common characteristic of such materials having a lower dielectric constant, however, is that the mechanical intensity of these materials is often lower than that of silicon oxide (SiO2). As a result, such materials having a lower dielectric constant are readily subject to physical shock and have a tendency to crack along or adjacent to the semiconductor devices during the step of performing the cutting process along the scribe-lines.
In one approach to these familiar problems, U.S. Pat. No. 6,441,465 to Chi-Fa Lin (the '465 patent), which is incorporated herein by reference, discloses a scribe line structure for preventing the type of damages as described above that may be induced during fabrication processes. According to the '465 patent, the scribe-line structure intentionally includes cavities disposed in a multi-layer structure along a scribe-line. The cavities are disposed on each side of a scribe-line and then disposed in at least two rows. The '465 patent teaches that such cavities reduce and relieve internal stress of the scribe lines, which may be created during formation of the scribe-line and thus reduce the tendency for crack formation, peeling, delamination and dielectric fracture of the scribe lines during cutting of the substrate.
However, the scribe-line structure taught by the '465 patent also can cause damage to the semiconductor devices because the cavities act as starting points for a crack during performing a cutting process along a scribe-line. Besides, the cavities also act as obstructions while performing the cutting process along the scribe-line, so that the processing time may be made longer than would otherwise be required.
These and other problems with or limitations of the prior art techniques in this field are addressed in whole, or at least in part, by the structures and methods of this invention.